I developed a patch to enable explicit support for the bladeRF XB300 amplifier in gr-osmosdr. I was surprised to find after purchasing one that this wasn't already integrated. Previously, the only way to configure these settings was to first run a separate bladeRF-cli script. I'm using this build in GNU Radio for R&D purposes and it works great; hopefully others find it as useful as I do.

Attached (tar): git-generated patch file, the two modified source files, and a readme primer. The two modified files are ~/lib/bladerf/bladerf_common.{cc,h}.